Elevated Serum Bilirubin Level Correlates With the Development of Cholangiocarcinoma, Subsequent Liver Transplantation, and Death in Patients With Primary Sclerosing Cholangitis

Primary Sclerosing Cholangitis: Epidemiology, Diagnosis, and Presentation

Primary sclerosing cholangitis (PSC) is considered an immunologically mediated disease. However, some of its features are not consistent with the typical profile of autoimmune conditions. PSC is characterized by progressive biliary fibrosis that may ultimately result in the eventual development of cirrhosis. In recent years, multiple studies have reported that the incidence and prevalence of this disease are on the rise. Consequently, patients are often diagnosed without symptoms or signs of advanced liver disease, although many still present with signs of decompensated liver disease. This article discusses the epidemiology, clinical presentation, and diagnostic workup in patients with PSC.

Independent of Primary Sclerosing Cholangitis and Cirrhosis, Early Adulthood Obesity Is Associated with Cholangiocarcinoma

BACKGROUND

It is estimated that 6% to 20% of all cholangiocarcinoma (CCA) diagnoses are explained by primary sclerosing cholangitis (PSC), but the underlying risk factors in the absence of PSC are unclear. We examined associations of different risk factors with intrahepatic cholangiocarcinoma (ICC) and extrahepatic cholangiocarcinoma (ECC) in the United States.

METHODS

We conducted a case-control study of 121 patients with ECC and 308 patients with ICC treated at MD Anderson Cancer Center between May 2014 and March 2020, compared with 1,061 healthy controls. Multivariable logistic regression analysis was applied to estimate the adjusted OR (AOR) and 95% confidence interval (CI) for each risk factor.

RESULTS

Being Asian, diabetes mellitus, family history of cancer, and gallbladder stones were associated with higher odds of developing ICC and ECC. Each 1-unit increase in body mass index in early adulthood (ages 20-40 years) was associated with a decrease in age at diagnosis of CCA (6.7 months, P < 0.001; 6.1 months for ICC, P = 0.001; 8.2 months for ECC, P = 0.007). A family history of cancer was significantly associated with the risk of ICC and ECC development; the AORs (95% CI) were 1.11 (1.06-1.48) and 1.32 (1.01-2.00) for ICC and ECC, respectively.

CONCLUSIONS

In this study, early adulthood onset of obesity was significantly associated with CCA and may predict early diagnosis at younger age than normal weight individuals.

IMPACT

The study highlights the association between obesity and CCA, independent of PSC. There is a need to consider the mechanistic pathways of obesity in the absence of fatty liver and cirrhosis.

Predicting cholangiocarcinoma in primary sclerosing cholangitis: using artificial intelligence, clinical and laboratory data

BACKGROUND

Primary sclerosing cholangitis (PSC) patients have a risk of developing cholangiocarcinoma (CCA). Establishing predictive models for CCA in PSC is important.

METHODS

In a large cohort of 1,459 PSC patients seen at Mayo Clinic (1993-2020), we quantified the impact of clinical/laboratory variables on CCA development using univariate and multivariate Cox models and predicted CCA using statistical and artificial intelligence (AI) approaches. We explored plasma bile acid (BA) levels' predictive power of CCA (subset of 300 patients, BA cohort).

RESULTS

Eight significant risk factors (false discovery rate: 20%) were identified with univariate analysis; prolonged inflammatory bowel disease (IBD) was the most important one. IBD duration, PSC duration, and total bilirubin remained significant (p < 0.05) with multivariate analysis. Clinical/laboratory variables predicted CCA with cross-validated C-indexes of 0.68-0.71 at different time points of disease, significantly better compared to commonly used PSC risk scores. Lower chenodeoxycholic acid, higher conjugated fraction of lithocholic acid and hyodeoxycholic acid, and higher ratio of cholic acid to chenodeoxycholic acid were predictive of CCA. BAs predicted CCA with a cross-validated C-index of 0.66 (std: 0.11, BA cohort), similar to clinical/laboratory variables (C-index = 0.64, std: 0.11, BA cohort). Combining BAs with clinical/laboratory variables leads to the best average C-index of 0.67 (std: 0.13, BA cohort).

CONCLUSIONS

In a large PSC cohort, we identified clinical and laboratory risk factors for CCA development and demonstrated the first AI based predictive models that performed significantly better than commonly used PSC risk scores. More predictive data modalities are needed for clinical adoption of these models.

Tissue-dependent transcriptional and bacterial associations in primary sclerosing cholangitis-associated inflammatory bowel disease

Background: Patients with primary sclerosing cholangitis (PSC) frequently have co-ocurring ulcerative colitis (UC) and develop colorectal cancer. Colorectal cancer risk in patients with PSC-associated ulcerative colitis (PSC/UC) is elevated relative to patients with ulcerative colitis (UC) alone, reasons for which remain obscure. Understanding the molecular and microbial basis for differences between these two patient groups and how these vary across intestinal sites is important for the development of therapies to prevent colorectal cancer development in at-risk individuals.   Methods: We employed ribonucleic acid sequencing (RNA-seq) analysis of biopsy samples across three intestinal tissue locations (ileum, caecum and rectum) in patients with PSC/UC (ileum n = 7, caecum n = 7, rectum n = 7), UC (ileum n = 9, caecum n = 10, rectum n = 10) and healthy controls (ileum n = 11, caecum n = 9, rectum n = 12) to determine tissue-dependent transcriptional alterations in PSC/UC. We also performed 16S ribosomal RNA (rRNA) amplicon sequencing to determine bacterial associations with PSC/UC. Results: Tissue-defining transcriptional signatures revealed that the ileum was enriched for genes involved in lipid and drug metabolism, the caecum for activated immune cells and the rectum for enteric neurogenesis. Transcriptional alterations relative to healthy control samples were largely shared between patients with PSC/UC or UC although were distinct across tissue locations. Nevertheless, we observed reduced expression of gamma-glutamyl transferase 1 ( GGT1) specifically in the ileum and caecum of patients with PSC/UC. Analysis of the bacterial component of the microbiome revealed high inter-individual variability of microbiome composition and little evidence for tissue-dependency. We observed a reduction in Parabacteroides relative abundance in the rectum of patients with PSC/UC. Conclusions: The role of gamma-glutamyl transferase in maintaining the redox environment through the glutathione salvage pathway makes our observed alterations a potential pathway to PSC-associated colorectal cancer.

Tissue-dependent transcriptional and bacterial associations in primary sclerosing cholangitis-associated inflammatory bowel disease

Background: Primary sclerosing cholangitis (PSC) is a disease of the bile duct and liver. However, patients frequently have co-morbidities including inflammatory bowel disease (IBD) and colorectal cancer. Colorectal cancer risk in patients with PSC-associated ulcerative colitis (PSC/UC) is elevated relative to patients with ulcerative colitis (UC) alone, reasons for which remain obscure. Further, clinical and immunological features, and involved intestinal sites differ between PSC/UC and UC. Understanding the molecular and microbial basis for differences in cancer risk between these two patient groups and how these differ across intestinal sites is important for the development of therapies to prevent colorectal cancer development in at-risk individuals.   Methods: We employed ribonucleic acid sequencing (RNA-seq) analysis of biopsy samples across three intestinal tissue locations (ileum, caecum and rectum) in patients with PSC/UC (n = 8), UC (n = 10) and healthy controls (n = 12) to determine tissue-dependent transcriptional alterations in PSC/UC. We also performed 16S ribosomal RNA (rRNA) amplicon sequencing to determine bacterial associations with PSC/UC and host-microbiome associations. Results: Tissue-defining transcriptional signatures revealed that the ileum was enriched for genes involved in lipid and drug metabolism, the caecum for activated immune cells and the rectum for enteric neurogenesis. Transcriptional alterations relative to healthy control samples were largely shared between patients with PSC/UC or UC although were distinct across tissue locations. Nevertheless, we observed reduced expression of gamma-glutamyl transferase 1 ( GGT1) specifically in the ileum and caecum of patients with PSC/UC. Analysis of the bacterial component of the microbiome revealed high inter-individual variability of microbiome composition and little evidence for tissue-dependency. We observed a reduction in Parabacteroides relative abundance in the rectum of patients with PSC/UC. Conclusions: The role of gamma-glutamyl transferase in maintaining the redox environment through the glutathione salvage pathway makes our observed alterations a potential pathway to PSC-associated colorectal cancer.

Challenging biliary strictures: pathophysiological features, differential diagnosis, diagnostic algorithms, and new clinically relevant biomarkers - part 1

It is frequently challenging to make the correct diagnosis in patients with biliary strictures. This is particularly important as errors may have disastrous consequences. Benign-appearing strictures treated with stents may later be revealed to be malignant and unnecessary surgery for benign strictures carries a high morbidity rate. In the first part of the review, the essential information that clinicians need to know about diseases responsible for biliary strictures is presented, with a focus on the most recent data. Then, the characteristics and pitfalls of the methods used to make the diagnosis are summarized. These include serum biomarkers, imaging studies, and endoscopic modalities. As tissue diagnosis is the only 100% specific tool, it is described in detail, including techniques for tissue acquisition and their yields, how to prepare samples, and what to expect from the pathologist. Tricks to increase diagnostic yields are described. Clues are then presented for the differential diagnosis between primary and secondary sclerosing cholangitis, IgG4-related sclerosing cholangitis, cholangiocarcinoma, pancreatic cancer, autoimmune pancreatitis, and less frequent diseases. Finally, algorithms that will help to achieve the correct diagnosis are proposed.

Recent developments in the research on biomarkers of cholangiocarcinoma in primary sclerosing cholangitis

Primary sclerosing cholangitis (PSC) is characterized by a chronic inflammatory process of the bile ducts of unclear aetiology. It is often complicated by cholangiocarcinoma (CCA) with a dismal prognosis. Early detection of CCA is important because treatment options for advanced disease are limited. Besides the established markers, like CA19-9, recent developments have been made using latest technologies. This review summarizes the recent advances and remaining limitations of biomarkers of CCA in PSC.

Albumin-Bilirubin Grade as a Novel Predictor of Survival in Advanced Extrahepatic Cholangiocarcinoma

Aim

Child-Pugh (CP) grade has been used to assess liver function and postoperative outcomes in biliary tract neoplasms. The aim of this study was to preliminarily explore the prognostic significance of an alternative model of liver function, called albumin-bilirubin (ALBI) grade, in patients with extrahepatic cholangiocarcinoma (EHC).

Methods

A total of 109 advanced EHC patients, who received percutaneous transhepatic biliary stenting combined with iodine-125 seed implantation from January 2012 to April 2017 in our department, were enrolled. Preoperative clinical data were collected to calculate the CP and ALBI grades. The performance of ALBI score in predicting postoperative death was compared with that of CP score by using the receiver operating characteristic (ROC) curve. Kaplan-Meier analysis and Cox regression model were performed for overall survival (OS) analysis.

Results

The median survival time of our cohort was 12 months, and the 1-year and 2-year survival rates were 56.9% and 12.8%, respectively. The area under the ROC curve of ALBI score for predicting death was significantly greater than the CP score (0.751, 95% CI: 0.641-0.861, P < 0.001 vs. 0.688, 95% CI: 0.567-0.809, P < 0.001). The univariate analysis revealed that the factors related to overall survival of EHC were carbohydrate antigen 19-9, total bilirubin, albumin, ALBI grade, and CP score. In multivariate analysis, ALBI grade (HR = 1.65, 95% CI: 1.04-2.61, P = 0.032), but not CP score, was identified as an independent prognostic model.

Conclusion

We demonstrated that the ALBI grade could be used as a predictor of survival in unresectable EHC patients.

Biliary Intraepithelial Neoplasia (BilIN) in Primary Sclerosing Cholangitis: The First Report from Iran

BACKGROUND

Primary sclerosing cholangitis (PSC) as one of the most common chronic cholestatic liver diseases is a main predisposing factor for the development of cholangiocarcinoma (CCA). Biliary intraepithelial neoplasia (BilIN) is defined as precancerous bile duct epithelial changes, which can be eventually led to cholangiocarcinoma. There are very few studies about the frequency of BilIN in the patients with PSC and its correlation with paraclinical findings.

OBJECTIVES

In this study, we tried to find the frequency of BilIN in the patients with PSC and correlate its presence with clinicopathologic factors.

METHODS

During two years (2014 - 15) of investigation, 80 explanted livers with the confirmed diagnosis of PSC were studied through precise inspection and thorough sectioning of the explanted livers. These findings were correlated with paraclinical findings to identify any predictor of these neoplastic epithelial changes.

RESULTS

During the study period of 2 years, among 80 livers with confirmed diagnosis of PSC, there were 43 cases with different types of metaplasia. The frequency of epithelial changes was as below: 29 (35%) for pyloric metaplasia, 9 (10.8%) for mucinous metaplasia, 3 (3.6%) for intestinal metaplasia, 1 (1.2%) for osteoid metaplasia, and 1 (1.2%) for squamous metaplasia. There was no epithelial dysplasia in the study sample; however, according to the most recent reports, mucinous metaplasia is considered as BilIN 1; therefore, there would be 9 cases of BilIN I. There has been no statistically significant difference between PSC cases and those with BilIN in demographic variables, except for bilirubin and CA19-9 which were higher in the PSC cases with BilIN.

CONCLUSIONS

This study showed that the frequency of BilIN was low among Iranian patients with PSC. High bilirubin and CA19-9 can be predictors of the development of bile duct epithelial changes in patients with PSC.